Wharf fender



W. P. KINNEMAN Oct. 13, 1953 WHARF FENDER 5 Sheets-Sheet 1 Filed 001.. 21, 1952 INVENTOR. T WLL/AM P KNNEM/HV- M M Arro/v/vc-rs.

BY W Oct. 13, 1953 w N M v 2,655,005

WHARF' FENDER Filed Oct. 21, 1952 5 Sheets-Sheet 2 [will xillllllm I,

INVENTOR. W/LLMM P fU/v/vEMA/v M MwkW A TTORNEVJ.

Oct. 13, 1953 w. P. KINNEMAN WHARF FENDER 5 Sheets-Shea Filed Oct. 21, 1952 INVENTOR. WL L IA M P/(IN/VEM/IM BY W M Patented Oct. 13, 1953 UNITED STATES PATENT OFFICE WHAB DE William B. Kinneman, Westfield, N. J., assig'nor to Raymond Concrete Pile Company, New York, N. Y.,' a corporation of New Jersey Application October .21, 1952, Serial No. 315.944

11 Claims. 1

hi entio at s. 39 5 1. 061. s ru tures and a an ts for Wh r es. i rs h like In the de i n of al s ruc ur s u ed or m in ships a on si it h ong e c tom r practice to e o e me ho 9f rote ti th shi from da ue o co li on be we n. t e shi and the structure. Such damage may occur both dur the p i d. of d in th s i n l ring he pe d hen t m or d o he h rf bul head. While there is probably no practical means for insuring protection of the ships bow and the wharf structure from serious head-on collisions, Yet it is important to provide some system of fendering which will eliminate so far as Q$ bl m s d e: 9 r i r 90 5 01 5. nd the usual buifeting caused by the surge and wind forces during the" period while the ship is tied to the wharf. Present day ship schedules involving high speeds and very rapid turn-arounds are such that any delays due to even small injuries to the ships will involve heavy expenses. To minimize such injuries, wharf fendering syse tems should perform three main functions. First,

they must be capable of cushioning and quickly absorbing great amounts of energy, during several inches of movement when a ship collides with the fender at any angle, from straigh 0 .1 to broadside. Secondly, it is equally important that the fendering system be such as to widely distribute over a substantial portion of the wharf structure, the. concentrated blows due to a ship striking at any angle. The third important function is to reduce abrasion damage between the wharf and the ship while the latter is moored.

In typical cases Wharf tendering systems must be able to withstand the inertia of ships of 20,000 tons or more, moving at the rate, say, of one foot or more per second, and thus the structure must not only be capable of withstanding and distributing forces which are of. a magnitude greater than and of a nature different from those met with by shock absorbing means for any other purposes, but at the same time the fendering system must be ableto minimize the abrasive action, and withstand longitudinal thrusts of the moored ship, due, to tides. currents andv wind forces.

Aside from the common expedients of using mats, rope, old rubber tires and the like for the purpose, various attempts have. been. made to solve. the problem by using steel springs, hydraulic shock absorbers, heavy weights and. floating tanks, but such arrangements, unless made unduly complicated and expensive, are. incapable of satisfactorily and permanently meeting all of the above mentioned requirements of a satisfac- Itqr der n s m But by the present invention these requirements may all be fulfilled by providing a frame- Work along the edge of the wharf in spaced relation thereto, and with cushioning means interposed at suitable intervals between such framework and the edge of the wharf, such cushioning means involving the use of rubber so arranged and bonded to metal plates that the energy of the collisions will largely be absorbed and also distributed among adjacent cushioning units, by applying the forces to the rubber in a direction tending to subject the rubber to a shearing effect and also preferably at the same time to some xt t ca sing com ressi f. h rubber- It is now possible in various well known ways securely to. bond sheets or strips of rubber between two metal plates applied to the surfaces thereof, and it is possible to utilize rubber sandic ed be e n m p e i t is. w w the rubber working in shear with greater advantages than when the rubber is arranged to utilize its cushioning effect by subjecting it merely to direct compression. I have determined that for the purposes of providing cushioning means for wharf fendering Systems, the use of rubber in shear is capable of providing a surprisingly satisfactory support for wharf fendering frameworks, to withstand both the effects of collisions of the ship at various angles as well as the longitudinal forces of the ship when pressing against the fendering framework.

The framework preferably is faced with wooden timbers and is supported by a series of piles.

Various further and more specific obiects, features and advanta es of the invention will ap ear from the following description, taken in connection with the accompanying drawings illustrating by way of example the presently preferred embodiments of the invention.

In the drawings:

Fig. l is a plan view showing a preferred form of tendering arran ement constructed in accordance with the invention;

Fig. 2 is; a plan. view on a lar er scale showing furtherdetails of a preferred form of cushioning unit for the system of Fig. 1;.

Fig. 3 is a side view of one of the cushioning units and showing the manner in which same may be. secured with respect to the edge of a wharf and to the fendering framework:

Fig. 4 is aface view of one of the rubber pad and metal plate assemblies used in forming the cushioning unit of'Fig. 2;

Fig. 5 is a sectional view taken substantially along line 55 of Fig. 4;

Fig. 6 is a sectional view showing the manner in which assemblies such as of Fig. 5 may be secured to each other;

Fig. 7 is a perspective view of a Wedge block embodied in the assembly of Fig. 2;

Fig. 8 is a horizontal sectional view of a modified form of cushioning unit;

Fig. 9 is a sectional view taken along line 9-9 of Fig. 8; and

Fig. 10 is a horizontal sectional view of another modified form of cushioning unit.

Referring now to Figs. 1-3 in further detail, an edge of a concrete wharf or dock is indicated at H, a fendering framework formed of steel I- beams or the like is indicated at l2 faced along its upper outer edge with wooden timber as at l3, the framework being supported as by a plurality of piles l5 so driven into the mud at the bottom of the body of water that the upper portions thereof and the framework carried thereby will be free to flex somewhat toward or away from the wharf face. A plurality of the abovementioned cushioning units are indicated at l6 interposed at spaced points along between the framework and the wharf.

A ship is indicated at H in Fig. 1 in a position about to be moored to the wharf. The steel sides of the ship while riding at its mooring will gradually cause abrasion of the timbers 13, but such abrasion will be substantially less than would be the case if the framework were not backed by the cushioning units, and in any event as the timber eventually becomes worn away, it may readily be replaced at comparatively small cost, as may also the wooden piles l5 if same become unduly worn. The steel framework I2 is preferably so constructed as to be fairly rigid when subjected to small forces and yet when subjected to forces involving the inertia of a heavy ship, the framework wil1 yield to the extend permitted by the cushioning units l6.

Each of the cushioning units preferably comprises, as best shown in Fig. 2, a pair of spacedapart abutments as at 20, 2| formed by Welding together steel plates to provide housing-like structures, such as shown, and which may be secured to the wharf as by anchor bolts 22. Each unit also includes a wedge block member as at 23 also formed by welding together steel plates to provide a structure in the form shown in Fig. '7 for example, and which is attached to the fender framework at by bolts 25, preferably in the case of each unit, at a point opposite one of the piles [5. Also preferably as shown in Figs. 1 and 3, vertically positioned I-beams as at 26, 21 are so located as to be positioned between one of the piles and the point of attachment of the corresponding cushioning unit.

Between the wedge block member 23 and each of the abutments 20, 2|, a series of cushioning elements is arranged, these being of aconstruction which will now be described in connection with Figs. 4 and 5. That is, as shown in section in Fig. 5, a layer of rubber as at is interposed between and securely bonded to a pair of steel plates as at 3!, 32 to provide a so-called sandwich, a face view of which appears in Fig. 4. The steel plates at their edges extend out beyond the rubber and are provided with bolt holes whereby pluralities of these sandwiches may be secured together in the manner shown in Fig. 6 by bolts as at 33, and similarly secured by bolts 4 to flanges on the abutments 20, 2| and the wedge block 23 as indicated in Fig. 2.

As above indicated, the rubber may be securely bonded to the steel plates for example after brass plating the latter, in various ways which are well known and thus need not here be described, but which will assure such a firm bonding action that when such rubber sandwiches are subjected to powerful forces in shear, one of the steel plates will be yieldably movable generally parallel to the other without destroying the bond to the rubber, and thus providing a highly resilient cushioning means which will absorb great amounts of energy.

As shown in Fig. 2, the pluralities of these sandwich plates are bolted to the abutments and the wedge block in positions sloping slightly away from a vertical plane normal to the vertical surface of the wharf. This angle may vary for example from about 30% to about 45% depending upon the total required deflection and the desired maximum angle of distortion of the rubber. And the angle is such that when a ship collides with the framework head on, or at any fairly actute angle, the deflection of the rubber under the resulting load will be largely in shear, although to some extent also in compression. It will be appreciated that if the plates or sandwiches were all set normal to the wharf face, the rubber would be in pure shear and under some tension during its extreme deflection when a ship collides with the framework head on.

Thus in order to provide a desirable factor of safety against failure, the sandwich plates are preferably set at a small angle such that, even with a head on collision, the rubber is placed under some compression as well as in shear, and by so doing the possibility is avoided of ever placing the rubber under any such tension as might be destructive thereto during any normal operation of the fendering system. Furthermore, with the rubber sandwich means positioned as shown in Fig. 2, it will be apparent that the cushioning units will also be highly effective in resisting and cushioning longitudinal rubbing forces of heavy ships when moored parallel and under pressure against the wharf front. For these reasons the construction provides a substantial advantage over fender cushioning means heretofore proposed in the form of steel coil springs or volute springs, as well as a substantial advantage over other types of spring or resilient buffers which were only able effectively to resist or cushion the forces normal to the wharf.

In a typical case such as shown in Fig. 2, the steel framework is spaced about three feet from the edge of the wharf and the minimum distance between the faces of the two abutments 20, 2| is a little over four feet. The vertical dimension of the cushioning unit (as viewed in Fig. 3) of such example is about 18 inches. Each of the rubber sheets 30 is about three inches thick. Such a unit is calculated to permit inward cushioning movement of the steel framework through .a distance of about one foot. It will be apparent that if a ship collides with the framework at any substantial angle to the normal, the component of the resulting force along the direction of the face of the wharf will cause one of the two series of sandwiches to be subjected to heavy compression while at the same time the component of force normal to the wharf face will largely be absorbed by placing the rubber in shear and by pushing the wedge block portion of the unit toward the wharf, with the result of wedging both QUBBfObB of "the series of sandwiches respectively toward their abutmentswhereby neither "of 'the two series can become subject to tension.

The total deflection of thecu'shioning units is determined by the thickness, number "and offset angles of the rubber sandwiches, the durometer hardness'of the rubber controlling the relation between the deflection and the load, preferably rubber having a durometer hardness of 60 is used,'although'the hardness may vary between and80.

With the rubber members shaped and pcsie tioned as shown-in Figs. Z'and 6, substantially all of the rubber in the device is equally loaded and fully worked when subjected to its maximum deflection. The unit is therefore eflicient in the use of rubber, and since the maximum blows of a ship are infrequent and surging forces are small, the problem of heat dissipation is insignificant. The loading is temporary and will produce no permanent deformation of the rubber.

In case the wharf is one which is used for oil tankers, then neoprene or other suitable synthetic rubber or rubber-like materials may be used to avoid softening from oil spillage. In case units of the type above described have in acidi 'tion to ease of maintenance and avoidance of er;- cessive expense, several other advantages as compared with spring or other types of mechanisms heretofore proposed for the purpose, in that relatively heavy and frictionally engaging moving parts are avoided, thus avoiding wear and the necessity of lubrication. Also no close clearances are involved which would tend to be fouled bydebris falling from the wharf er ships, and if failure should occur in any one of the rubber sandwiches, it can easily be replaced without dismantling the entire device. Misalignnient of the parts is impossible once the units are installed and there are no guides 'or plungers to jam or bind.

The invention is adapted not only for use on the usual types of wharves and piers, but also on ferry docks and bridges, bridge fenders, dolphins and the like, all of which are intended to be referred to by the term wharf as used in the appended claims.

While the cushioning units of the type shown in Fig. 2 are preferred as best meeting the requirements for wharf rendering purposes with the most economical use of the rubber and for convenient manufacture, alternative arrangements for utilizing rubber in shear for the purpose are shown in F-igs. 8l0. For example in Fig. 8, annular rubber elements as at 40, iii are shown as bonded interiorly to attached cylindrical elements as at 42, M and bonded externally to at.- tached cylindrical elements its and t5, the inner cylindrical steel element being secured to fendering framework as at it and the outer cylindrical steel member being secured as shown to the edge of a clock 4?. In this way two or more rubber members may be arranged in effect in tandem and in a manner such that the rubber is placed in shear when ships collide head on, or at an acute angle with the fendering framework, the rubber also being subjected to compression, if the force 6 or thesnip has an important component longitridinally or the dock. From Fig. 8 it willbe-noted that the rubberi's' m ade thicker around the inner cylindrical members 42, t3 than at the peripheral portions. The thickness'niig-ht of -coursebe madethe same at the inner andouterportionsof these annular rubber members, and then in that event the rubber adjacent the inner cylinders would be worked to a higher shear stress than at the'outer cylinder surfaces and-hence the rubher would not be as efficiently used as when the rubberelements-are shaped as shown in Fig. 8.

In the einbodiinent shown in Fig. 10, annular rubber members as at 50, 51 and 52 are shown as bonded respectively in between cylindrical steelmembers di -=54, 55==56 and 5 1 -58, these cylindrical members being arranged in stepped relation as shown: and so as to provide with the rubber elements sandwichedt-herebetween, an arrangement which in cross section is somewhat similar to that of Fig. 2, but being annular in form, it will be able to resist equally well not only longitudinal horizontally directed forces, but also forces parallel to the face of the dock either directed upwardly or downwardly, or at various angles to the vertical. It will be noted that the upper end surface of the rubber elements as shown Fig. 10 form truncated cones, for the same reason as above explained in connection with the rubber elements of Fig. 8. Also the lower surfacesof the rubber elements as shown in Fig. 10 are curved in cross-section in such a manner as to cause substantially uni-form working of all of the rubber when subjected to shear. The construction of Fig. 10 may be mounted upon and secured to the dockand to the fendering framework in a manner whichwill be readily apparent from the drawing. It will also be apparent that with each of the embodiments shown, the broader portion of the cushioning unit may be mounted on the fendering framework instead of being mounted on the face of the dock, and the more pointed portion of the cushioning unit would then, of course, be secured to the dock.

Although certain particular embodiments of the invention are herein disclosed for purposes of explanation, various further modifications thereof, after study of this specification, will be apparent to those skilled in the art to which the invention pertains. Reference should accords ingl'y be had to tneappended claims in determining the scope of the invention.

What is claimed and desired to be secured by Letters Patent is:

1. In a wharf fendering arrangement the combination of a fender-ing framework supported on piles and extending longitudinally of and in spaced relation to the face of a wharf, a plurality of cushioning units mounted between said framework and the wharf at 'spa-ced positions, each of said units comprising a pair of spaced apart abutments mounted at one side of the space between the framework and wharf, a wedge block means mounted at the other side of said space "and at a position intermediate said abutments, the opposite sides of said wedge block means having faces positioned to provide a wedge directed into the space between the abutn'rents and the 'abutments having faces respectively opposed to the wedge block faces, and a series of cushionin'g elements interposed between each such wedge block face and the corresponding abutment face, said elements comprising sandwiches of rubber bonded to metal plates, the parts being shaped and positioned whereby upon collisions of ships against the framework, the force thereof will be distributed by the framework to said cushioning units and a, substantial part of the force will be absorbed by subjecting the rubber to forces in a direction tending to apply a shearing effect thereto and at the same time to some extent causing compression of the rubber.

In a wharf fendering arrangement, the combination of a fendering framework formed of beams extending longitudinally of and in spaced relation to the face of a wharf, a plurality of cushioning units mounted between said framework and the wharf at spaced positions, each of said units comprising at least one body of rubber having its opposite surface areas respectively bonded to surface areas of metal members, which are transverse to the face of the wharf, one of said metal members being mounted at the wharf face and the other at the framework, whereby upon collisions of ships against the framework, the force thereof will be distributed by the framework to said cushioning units and absorbed at least to a substantial extent by subjecting the rubber to forces in a direction tending to apply a shearing effect thereto.

3. In a wharf fendering arrangement, the combination of a fendering framework extending longitudinally of and in spaced relation to the face of a wharf, said framework being constructed and supported so as to be somewhat yieldable in directions normal to the face of the wharf when subjected to forces of ships colliding with or pressing against same, and a cushioning unit mounted between said framework and the wharf, such unit comprising a plurality of bodies of rubber each having opposite surface areas thereof bonded to surface areas of metal members, the bonded surfaces being positioned transversely to the face of the Wharf, the metal member which is bonded to one surface of each rubber body being mounted to subject the rubber to a shearing effect inwardly of the face of the wharf when the framework is pressed inwardly, and the metal member bonded to the other surface of each rubber body being mounted to subject the rubber to a shearing force outwardly of the wharf as a result of the reaction of the wharf against the force of ships engaging the framework.

4. In a wharf fendering arrangement the com bination of a framework extending longitudinally of and in spaced relation to the face of a wharf, a plurality of cushioning units mounted between said framework and the wharf at spaced positions, each of said units being of generally V-shape, with each side of the V extending from the wharf to said framework, and each such side including a series of superposed sandwiches comprising layers of rubber each having its opposite surfaces bonded to the surfaces of metal plates, such sandwiches being positioned substantially along vertical planes transverse to the face of the wharf, and at such angles with respect to the wharf face that forces of ships pressillg against said framework will subject said rubber to forces in a direction tending to apply both shearing and compression effects thereto.

5. In a wharf fendering arrangement, the combination of a fendering framework extending longitudinally of and in spaced relation to the face of a wharf, said framework being constructed and supported so as to be somewhat yieldable in directions normal to the face of the wharf when subjected to forces of ships collidin with or pressing against same, and a cushioning unit mounted between said framework and the wharf, said cushioning unit comprising at least two substantially coaxial partially telescoping tubular metal members of different sizes mounted respectively at the wharf face and at the framework, and bodies of rubber in the spaces between said tubular members and each having internal and external surfaces respectively bonded to surfaces of said tubular members whereby forces imparted by ships colliding with or pressing against said framework will subject such rubber to forces in a direction tending to apply a shearing effect thereto.

6. In a wharf fendering arrangement, the combination of a fendering framework extending longitudinally of and in spaced relation to the face of a wharf, said framework being constructed and supported so as to be somewhat yieldable in directions normal to the face of the wharf when subjected to forces of ships colliding with or pressing against same, and a cushioning unit mounted between said framework and the wharf, such unit comprising a plurality of bodies of rubber each having opposite surface areas thereof bonded to surface areas of metal members, said metal members being so positioned and mounted as to subject the rubber to a shearing effect as a result of such forces.

7. In a wharf fendering arrangement, the combination of a fendering framework extending longitudinally of and in spaced relation to the face of a wharf, said framework being constructed and supported so as to be somewhat yieldable in directions normal to the face of the wharf when subjected to forces of ships colliding with or pressing against same, and a cushioning unit mounted between said framework and the wharf, such unit comprising a plurality of bodies of rubber each having opposite surface areas thereof bonded to surface areas of metal members, said metal members being so positioned and mounted as to subject the rubber to a shearing effect as a result of such forces, and said rubber bodies as so bonded being of such cross-sectional shape that the rubber thereof will be substantially uniformly stressed by the action of said forces.

8. A cushioning unit for wharf fendering purposes, such unit being of a generally /-shape with a metal wedge block at the vertex of the V, the opposite sides of said wedge block having faces positioned to provide wedging action directed toward the space between the sides of the V, metal abutment members at the ends of such sides and having surfaces approximately parallel to said wedge faces respectively, and a series of superposed layers of rubber interposed respectively between each of said wedge faces and said abutment surfaces, each of said layers of rubber having its opposite surfaces bonded to metal plates to form rubber and metal sandwiches, the sandwiches being secured together in a superposed series by, and each series being connected to the wedge block and to its abutment by bolts passing through the peripheries of the metal plates.

9. A cushioning unit for wharf fendering purposes, such unit being of a generally V-shape with a metal wedge block at the vertex of the J, the opposite sides of said wedge block having faces positioned to provide wedging action directed toward the space between the sides of the V, metal abutment members respectively at the ends of such sides, and a series of superposed layers of rubber interposed respectively between each of said wedge faces and said abutments, each of said layers of rubber haVing its opposite surfaces bonded to metal plates to form rubber and metal sandwiches, such sandwiches extending along planes approximately parallel to said wedge faces.

10. In a wharf fendering arrangement, the combination of a fendering framework extending longitudinally of and in spaced relation to the face of a wharf, said framework being constructed and supported so as to be somewhat yieldable in directions normal to the face of the wharf when subjected to forces of ships colliding with or pressing against same, and a cushioning unit mounted between said framework and the wharf, said cushioning unit comprising a plurality of substantially coaxial partially telescoping metal cylinders of different sizes, one being mounted at the wharf face and another at the framework, and bodies of rubber in the spaces between said cylinders and each having internal and external surfaces respectively bonded to surfaces of said cylinder whereby forces imparted by ships colliding with or pressing against said framework will subject such rubber to forces in a direction tending to apply a shearing effect thereto.

11. In a wharf fendering arrangement, the combination of a fendering framework extending longitudinally of and in spaced relation to the face of a wharf, said framework being constructed and supported so as to be somewhat yieldable in directions normal to the face of the wharf when subjected to forces of ships colliding with or pressing against same, and a cushioning unit mounted between said framework and the wharf, said cushioning unit comprising a plurality of substantially coaxial partially telescoping metal cylinders of different sizes, one being mounted at the wharf face and another at the framework, and bodies of rubber in the spaces between said cylinders and each having internal and external surfaces respectively bonded to surfaces of said cylinder whereby forces imparted by ships colliding with or pressing against said framework will subject such rubber to forces in a direction tending to apply a shearing effect thereto, and said rubber bodies as so bonded being of such cross-sectional shape that the rubber thereof will be substantially uniformly stressed by the action of said forces.

WILLIAM P. KINNEMAN.

No references cited. 

